Acquisition and extinction of a conditioned passive avoidance reflex in mice with genetic knockout of monoamine oxidase A

Abstract

We report here the results obtained from comparative analysis of learning and the dynamics of extinction of a conditioned passive avoidance response in mice with genetic knockout of monoamine oxidase A (MAO A) and the progenitor line C3H. Mice of both lines acquired the conditioned passive avoidance reaction efficiently. Mice with genetic knockout of MAO A were characterized by prolonged retention of reproduction of the memory trace, as compared with rapid extinction in C3H mice. Smaller numbers of transfers, and vertical rearings on days 7–13 and the numbers of glances into and rom the dark sector on days 11–13 of extinction in MAO A-knockout mice appear to reflect their more marked fear reactions when confronted with the “dangerous” sector, along with increased anxiety, these facilitating longer-lasting retention of the memory trace.

References

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